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Inventory	9 Months Ended
Inventory	Sep. 30, 2019
Inventory [Abstract]
Inventory	(15)INVENTORY Inventory is valued at lower of average cost or net realizable value (NRV). As of September 30, 2019 and December 31, 2018, coal inventory includes NRV adjustments of $2.7 million and $1.1 million, respectively